Abstract : Purpose: The objective of this study was to.evaluate the effect of different angulations of impacted maxillary canine on root resorption of lateral incisor using cone-beam computed tomography(CBCT). Methods and material : The sample included 30 CBCTs presenting with unilateral or bilateral impacted maxillary canines were evaluated ranging in age from 15 to 30 years that were selected and collected.from the Department of Radiology Faculty of Dentistry (Suez Canal University). Canine angulation relative to the maxillary occlusal plane and adjacent lateral incisor was measured, as well as the locations of the impacted canines. Results : The results of the current study showed (58.8 %) with slight resorption, and (26.5%) with moderate resorption of lateral incisor root. Lateral incisor root resorption was more common in the apical third and palatal surface. There was a statistically significant relationship between root resorption severity and angulation of impacted maxillary canine relative to the lateral incisor. Angle.of impacted maxillary canine with occlusal plane can`t be solely relied on determining the severity of root resorption (RR). Conclusion : RR occure due to.proximity.of impacted.maxillary canine to adjacent lateral incisor .Slight RR occur most commonly at apical and palatal surface.